Automotive vehicles require brakes in order to apply a force of friction against the road. Vehicles, for example heavy duty vehicles such as trucks, trailers, campers, buses, and other such heavy duty vehicles, require a substantial force to stop the vehicle from moving or to reduce the speed of the vehicle.
Rather than use traditional brake systems, heavy duty vehicles use air brake systems, the air brakes having a housing design able to support a force great enough to reduce the speed of a heavy duty vehicle.
The prior art has deployed various housing designs that are able to accommodate such a force exerted upon the housing by an actuator or push-rod. However, prior art designs suffer from limitations as the prior art designs do not sufficiently accommodate for the shock and vibration stress exerted upon the housing.
Shock and vibration stress in combination with the typical stress concentrations are the primary reasons for material failure in such stud housing assemblies for heavy duty vehicle brake actuators. Thus, it is desirable to develop a system that can reduce the amount of shock and vibration in stud housing assemblies. It is further desirable to develop a system that dampens the shock and vibrations in the housing by applying a flexible adhesive material for load transfer in the housing assembly.
Prior art housings designs attempt to reduce stress and vibration, however, these designs have limited capability as such designs do not effectively reduce shock and vibration stress, and do not use a flexible adhesive material to assist with load transfer.
Prior art designs involve stamped metal stud housing assemblies and cast metal housing assemblies.
Cast metal housing assemblies have studs cast into the housing or attached by threading into or through the casting.
However, these cast metal housing assemblies, while being robust and typically not as prone to vibration and shock damage as stud type housings, are very heavy. The weight of the cast type housings make them uneconomical and inefficient for use in heavy duty vehicles. In industry, cast type housings are not widely used.
Stamped metal stud housings designs found in the prior art include stamped metal stud housing assemblies having studs rigidly attached directly to the housing shell by welding, swaging, and/or riveting. These designs may additionally have one or more reinforcing plates to limit vibration and stress.
U.S. Pat. No. 5,784,946 to Malosh et al. teach a housing with a central opening having a metal plate and a housing, with studs connecting the metal plate to the housing, and a foam membrane bonded thereto with an adhesive layer to dampen sound.
While the foam membrane and adhesive layer of Malosh et al. act to dampen sound, Malosh et al. do not teach a flexible adhesive material that reduces shock and vibration, while providing a permanent attachment for the reinforcing plate to the housing. Additionally, Malosh et al. do not teach load transfer for both compressive and tensile forces.
U.S. Pat. No. 4,409,460 to Nishii et al. teach reinforcing a portion of a housing with an annular plate secured to the housing via bolts and an insulating layer. However, Nishii et al. do not teach a flexible adhesive material attached to the stud housing shell to reduce shock and vibration, while providing a permanent attachment of the reinforcing plate to the housing. Nishii et al. also do not teach load transfer for both compressive and tensile forces.
U.S. Pat. No. 5,072,607 to Kaneko teaches a housing with a reinforcement plate, the reinforcement plate clamped between the shell and mounting plate to improve vibration/insulating properties. However, Kaneko also does not teach a flexible adhesive material attached to the stud housing shell to reduce shock and vibration, while providing a permanent attachment of the reinforcing plate to the housing. Kaneko also does not teach load transfer for both compressive and tensile forces.
The prior art fails to provide the advantage of a flexible adhesive material, which provides a permanent attachment of the reinforcing plate to the housing. The prior art additionally fails to teach load transfer for both compressive and tensile forces.
Therefore, it is desirable to provide a vibration and shock resistant stud housing design for stud mounted brake actuators that has a flexible adhesive material set between the reinforcing plate and housing shell. It is further desirable to provide a stud housing design which incorporates threaded mounting studs which are rigidly attached to a separate reinforcing plate and subsequently attached to the stud housing shell with a flexible high strength adhesive material. It is further desirable that the flexible adhesive material consist of polymeric tape with high strength pressure sensitive adhesive on both sides, which is applied between the reinforcing plate and housing shell. It is further desirable that a permanent attachment is formed between the reinforcing plate and the housing shell that helps to avoid stress concentrations in the housing shell. It is further desirable that the stud housing design teach load transfer for both compressive and tensile forces.